Why You Need a "Locked Card"

A valuation answers "whether this stock is worth buying now"—a judgment made in a single moment. But real investing is a journey of years between when you buy and when you sell. Most people lose money precisely in this "middle stretch": prices move, news erupts, emotions swing, and the "reasons" you originally bought for quietly drift without your noticing.

The Locked Assumption Card exists to cure exactly this ailment. It is not a report you read and discard; it freezes the clarity of the moment you made your judgment into a holdable, reviewable investment discipline.

1. Lock In Assumptions, Prevent Drift

This is the Locked Card's most essential value. It freezes the required return, terminal assumptions, and scenario probabilities from when you bought, along with "under what circumstances I will admit I was wrong" (the Kill Criteria). Three months later, when the price has halved and everyone is calling it a sell, you will not improvise a reason to console yourself; you will go back and check the card: did the Kill Criteria you set actually trigger? Has the long-term logic really changed?—in essence, letting "the calm you" constrain "the panicked you."

“The investor's chief problem—and even his worst enemy—is likely to be himself.”— Benjamin Graham

2. Only What Can Be Reviewed Can Improve

The card records your original thesis, the data you used, and the moment you made the judgment (the decision journal). This lets you honestly review later: were you right or wrong at the time? Was it good luck, or was the judgment truly sound? Without this record in black and white, human memory automatically rewrites itself into "I knew it all along"—and so you never learn anything. Only decisions that can be reviewed can bring real progress.

3. Effortless Maintenance, Holdable for the Long Term

With a Locked Card, routine maintenance becomes easy and self-consistent: when new data arrives, a "data refresh" updates price and earnings while the long-term assumptions stay untouched; only when evidence genuinely changes the long-term logic do you go through a "valuation revision" to generate a new version, with a trail left throughout. This makes "holding a portfolio for the long term, with discipline" realistic for the first time—rather than recomputing from scratch each time or simply going on feel.

4. It Is Your Asset, and Portable

The Locked Card is stored under your own account, or written directly into your own GitHub repository. It belongs to you, is portable, and is auditable. Over time, you accumulate an entire "research card library" of your own—a knowledge asset that compounds in value. The platform owns "the rules and the ability to refresh correctly," while the content asset is always yours.

In One Sentence

The engine sells "one correct judgment," and the Locked Card provides "long-term investment discipline and a reviewable asset." The former is an instant; the latter is an entire journey. This is also the fundamental difference between this site and "asking an AI once and being done"—we help you turn investing into a process that continues, improves, and belongs to you.